"Reasonable" light weight spoke combinations for road

[Kontact]

I've built a fair number of wheels professionally and for myself, but not enough to say absolutely that X,Y or Z is the way to do it. The following are for 700c rim brake wheels.

So I've been thinking about what number and kind of spokes would be "reasonable" to minimize weight for a medium sized rider while not requiring frequent re-trues or any risk of broken spokes. Assuming the same model rim front and rear, thoughts:

You don't need as many spokes on the front wheel as rear. How many less is a real question. 4 down is the standard, like 24/28, but maybe 8 less would be smarter 24/32 or 20/28. This may be a question best answered by rim type or strength - 8 down for a 440 gram rim, but only 4 less for a 400g?

Spoke weight. The spokes working hardest are the rear drive side, and properly built 2/1.8/2 are the gold standard for strong spokes. So how about going lighter for the front and NDS? I have used 2/1.5/2 spokes for this purpose, but some sources say that 1.5 is too much of a wind-up problem. Brandt liked 1.8/1.6/1.8, which winds up less and is about as light. DT also makes a 2/1.6/2 if either is going too far.

To put the spoke weight thing in perspective, 24 2/1.5/2 spokes + nipples weigh less than only 20 2/1.8/2. 4 extra spokes supporting the rim just by using thinner spokes seems like a great deal. However, it is arguably less aero.

So if you wanted something "fast" that lasts, what's the minimum spokes you would use for someone 175 pounds, and why? (2:1 rear lacing is another wrinkle, but limited in available combinations.)

My current thinking is 20/28 on a 420 gram rim with 1.8/1.6/1.8 everywhere but the DS. (Mr. Cheap alternative - 15g straight with 14g straight DS.)

[ultraman6970]

It depends a lot of the rim you are going to use.

Is not the same go light 28/24 with a box rim than going the same with a 50 mm tall rim. And sure you can go super light with 28/24 box rim, the problem is that no matter the spoke you put in there the wheel wont be like super reliable.

[Gummee]

Depends on the rider. Some folks can ride 20/24s and be fine, but another guy that doesn't ride as smoothly will have problems with 24/28s

Also depends on the rim.

Since I ride lightly, I'm likely to go 20/24 on some aero rims or even some Belgium + rins

...but that's me. You'll have to talk to someone that's built more wheels than I have for more specific details

M

[Kontact]

Originally Posted by ultraman6970

It depends a lot of the rim you are going to use.

Is not the same go light 28/24 with a box rim than going the same with a 50 mm tall rim. And sure you can go super light with 28/24 box rim, the problem is that no matter the spoke you put in there the wheel wont be like super reliable.

I used 420 gram rims as an example. Where does that fall into your spectrum?

[cmbicycles]

Originally Posted by Kontact

I used 420 gram rims as an example. Where does that fall into your spectrum?

420g is fairly light for a rim. At that weight, assuming aluminum, it would be a box section rim. Carbon rims can be deeper section and come in 420g or less.

[Kontact]

Originally Posted by cmbicycles

420g is fairly light for a rim. At that weight, assuming aluminum, it would be a box section rim. Carbon rims can be deeper section and come in 420g or less.

Actually, for the last 30 years or so the light clinchers are all low aero or semi-aero rims like the Open4, Aerohead, Campy Ypsilon, Matrix Aero, DT RR415, Kinlin XR200, etc.

[cmbicycles]

Originally Posted by Kontact

Actually, for the last 30 years or so the light clinchers are all low aero or semi-aero rims like the Open4, Aerohead, Campy Ypsilon, Matrix Aero, DT RR415, Kinlin XR200, etc.

Open pro are around 435g I think, so close, and 20mm deep. Xr200 are 385g, 22mm deep, & not recommended for heavier riders. Aerohead hit the weight, but 19mm deep. DT 415 and campy rim aren't made any longer, and matrix rims (if made anymore) are/were junk imo. None of those are a deep section rim by any stretch so fall into the "box section" lightweight rim qualification (i.e. generally no low spoke counts for reliability) as far as I'm concerned when selecting wheel components.

[Kontact]

Originally Posted by cmbicycles

Open pro are around 435g I think, so close, and 20mm deep. Xr200 are 385g, 22mm deep, & not recommended for heavier riders. Aerohead hit the weight, but 19mm deep. DT 415 and campy rim aren't made any longer, and matrix rims (if made anymore) are/were junk imo. None of those are a deep section rim by any stretch so fall into the "box section" lightweight rim qualification (i.e. generally no low spoke counts for reliability) as far as I'm concerned when selecting wheel components.

The RR415 was replaced with the lighter RR411. The Sun CR17A is 410g. The Open Pro is 425g. Kinlin also makes an A frame rim at 406g and the American Classic CR350 is an absurd 350g.

What box section rim is 420 grams or lighter? Or are you calling an Aerohead a box section rim? The lightest actual box section rim I know of is the Omega at 425, but the MA40 is 440g, and neither was built for lower spoke counts.

[cmbicycles]

Originally Posted by Kontact

The RR415 was replaced with the lighter RR411. The Sun CR17A is 410g. The Open Pro is 425g. Kinlin also makes an A frame rim at 406g and the American Classic CR350 is an absurd 350g.

What box section rim is 420 grams or lighter? Or are you calling an Aerohead a box section rim? The lightest actual box section rim I know of is the Omega at 425, but the MA40 is 440g, and neither was build for lower spoke counts.

Open pro is claimed 425g, mine were all heavier if you want to split hairs. American classic is out of business, as I'm sure you know. I'm not claiming any of these are "true" box section rims, I'm saying that I lump them all together under that category and won't build them with fewer spokes to save weight at the expense of reliability, as that was the aim of your original question.

I gather you like to argue on these posts, so you do whatever you want with whatever rim you want and let us know how it turns out. I won't build low spoke wheels with any of the rims above, ymmv.

[Kontact]

Originally Posted by cmbicycles

Open pro is claimed 425g, mine were all heavier if you want to split hairs. American classic is out of business, as I'm sure you know. I'm not claiming any of these are "true" box section rims, I'm saying that I lump them all together under that category and won't build them with fewer spokes to save weight at the expense of reliability, as that was the aim of your original question.

I gather you like to argue on these posts, so you do whatever you want with whatever rim you want and let us know how it turns out. I won't build low spoke wheels with any of the rims above, ymmv.

Funny, I thought you were the one picking nits.


I have two pairs of XR-200 wheels in low spoke counts and saw and built a ton of Aeroheads as Crono wheels when I worked for the company that designed them - they were 24/28s.

I can understand why you wouldn't want to go to a low spoke count on a light rim, and it would be interesting to hear how you'd handle the questions posed in the thread instead of referring to box section rims that don't appear to exist and that no one builds in low spoke counts.

It sounds like you have a lot of wheelbuilding experience, so why don't we discuss how you would build wheels instead? You can pick whatever weight or spoke count you'd like to use as an example.

[oldpotatoe]

Originally Posted by Kontact

I've built a fair number of wheels professionally and for myself, but not enough to say absolutely that X,Y or Z is the way to do it. The following are for 700c rim brake wheels.

So I've been thinking about what number and kind of spokes would be "reasonable" to minimize weight for a medium sized rider while not requiring frequent re-trues or any risk of broken spokes. Assuming the same model rim front and rear, thoughts:

You don't need as many spokes on the front wheel as rear. How many less is a real question. 4 down is the standard, like 24/28, but maybe 8 less would be smarter 24/32 or 20/28. This may be a question best answered by rim type or strength - 8 down for a 440 gram rim, but only 4 less for a 400g?

Spoke weight. The spokes working hardest are the rear drive side, and properly built 2/1.8/2 are the gold standard for strong spokes. So how about going lighter for the front and NDS? I have used 2/1.5/2 spokes for this purpose, but some sources say that 1.5 is too much of a wind-up problem. Brandt liked 1.8/1.6/1.8, which winds up less and is about as light. DT also makes a 2/1.6/2 if either is going too far.

To put the spoke weight thing in perspective, 24 2/1.5/2 spokes + nipples weigh less than only 20 2/1.8/2. 4 extra spokes supporting the rim just by using thinner spokes seems like a great deal. However, it is arguably less aero.

So if you wanted something "fast" that lasts, what's the minimum spokes you would use for someone 175 pounds, and why? (2:1 rear lacing is another wrinkle, but limited in available combinations.)

My current thinking is 20/28 on a 420 gram rim with 1.8/1.6/1.8 everywhere but the DS. (Mr. Cheap alternative - 15g straight with 14g straight DS.)

First depends on rider..some light riders klll wheels and heavy riders can do with uber light wheels.
Second when you are talking 'saving weight', with things like spokes..you are talking about very, very little weight added or 'saved'...but thinner spokes, even more of them, will effect reliability.

For a 175 pound rider(...probably heavier than than unless he rides an 'air' bike, naked)..and if he thinks light thoughts..I'd do 24/28, Sapim Laser front and left side rear, Sapim Race right side rear..2 cross front, 3 cross rear, inside pulling on both..brass nipples. PLUS really good 420 gram rim, like DT411.

Even if found, I wouldn't use straight gauge spokes nor CX-Ray..CX-Ray(I know, not mentioned) lotsa $ for no real performance improvement.

[AngryScientist]

a wheel is a system of parts that work together, and you can't really discuss one part of that system in a vacuum, without looking at the whole build. Spoke count is only one part of the equation to a reliable wheel.

rim weight is not necessarily an indicator of stiffness or strength, and (in my opinion/experience) should not be used alone to determine a minimum number of spokes to build a wheel.

you have to look at it all, spoke count, hub selection/bracing angle, rim design, spoke tension, nipple selection - the whole thing - and balance it against the rider and the type of riding done on the wheel.

for example - i'm rolling on a sub 1400g wheelset, built 16/20 spokes - and they are dead reliable wheels.

this is where a real, experienced wheel builder's expertise comes into play. picking all the parts that work together, building them up properly and matching them to the rider and the riding is what makes a good handbuilt wheel.

or shamals. shamals are excellent wheels for anyone.

[cmg]

what's the rim weight of the Shamals? The King hubs carry a lot of the wheelset weight.


last wheel set I had built was 28 front, stans 340 rim and KINLIN r200 32 holed rear 3x both sides, sapim race on the front and non-drive rear and thicker on the drive side. i'm close to 200lbs and haven't had problems with them, but I don't throw them around corners or sling side to side on climbs. I've had AC sprinter 350 in the past and as long your reasonable with them they were fine. the AC wheels didn't take peddling through a corner at high speed well. so you can build with a lighter than 420-445 gram rim but spoke count needs to be higher for a heavier rider. my opinion..........

[Kontact]

Originally Posted by AngryScientist

for example - i'm rolling on a sub 1400g wheelset, built 16/20 spokes - and they are dead reliable wheels.

Please don't keep a secret. What are they made up of?


My lightest wheels are something like 1250 grams - XR200s, 20 front 1x, 24 rear 16:8 2x laced with CX-Rays all around.

[Ralph]

For reliable road riding.....do you mean in a group....not far from help.....where everyone has a cell phone....where wife at home is standing by.....or in a race....where you hold up a hand for help, etc?

Or do you mean reliable where you are off alone by yourself....on an all day adventure....or on long lonely ride, not necessarily loaded, but no one around for help either, or on a vacation on a ride by yourself, with no bike shops around to rebuild a wheel, etc?

I recently broke a front spoke on a Campagnolo Zonda....just riding along on a very smooth trail at about 12 MPH. I weigh 158. These are considered bullet proof, bomb proof wheels. Yet a spoke just broke. Got the wheel fixed, there was some sign I had hit something in past....some red paint there......but I don't consider these wheels bullet proof anymore. I take my 32/32 wheels on trips now. Figure most any bike shop can repair them.

Not meaning to be critical of your original question.....just stating I have changed my mind some about what I consider reliable wheels for various uses. And I am very easy on wheels. Good luck with your build.